Hi,
Welcome to ehealthforum,
It is difficult to comment on the cause for your absent periods after miscarriage without examining you and going ahead with further evaluation. You should consider visiting your doctor/gynecologist at the earliest for further evaluation and investigations. Hormonal tests done to rule out any hormonal derangements. Ultrasound scan done would help to see if the uterine cavity is empty. The blood HCG test would confirm if the levels have come back to pre-pregnancy levels. Treatment as needed (based on examination and investigations results) would be started to help you get back your periods and regulate them. Be in regular monitoring and follow-up with your treating doctor/gynecologist and report any new/abnormal symptoms immediately. Drink plenty of water. Take adequate rest.
Take care.